From: Logan Gunthorpe logang@deltatee.com
commit 3b7830904e17202524bad1974505a9bfc718d31f upstream.
kmemleak reports a memory leak with the ana_log_buf allocated by nvme_mpath_init():
unreferenced object 0xffff888120e94000 (size 8208): comm "nvme", pid 6884, jiffies 4295020435 (age 78786.312s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 ................ 01 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000e2360188>] kmalloc_order+0x97/0xc0 [<0000000079b18dd4>] kmalloc_order_trace+0x24/0x100 [<00000000f50c0406>] __kmalloc+0x24c/0x2d0 [<00000000f31a10b9>] nvme_mpath_init+0x23c/0x2b0 [<000000005802589e>] nvme_init_identify+0x75f/0x1600 [<0000000058ef911b>] nvme_loop_configure_admin_queue+0x26d/0x280 [<00000000673774b9>] nvme_loop_create_ctrl+0x2a7/0x710 [<00000000f1c7a233>] nvmf_dev_write+0xc66/0x10b9 [<000000004199f8d0>] __vfs_write+0x50/0xa0 [<0000000065466fef>] vfs_write+0xf3/0x280 [<00000000b0db9a8b>] ksys_write+0xc6/0x160 [<0000000082156b91>] __x64_sys_write+0x43/0x50 [<00000000c34fbb6d>] do_syscall_64+0x77/0x2f0 [<00000000bbc574c9>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
nvme_mpath_init() is called by nvme_init_identify() which is called in multiple places (nvme_reset_work(), nvme_passthru_end(), etc). This means nvme_mpath_init() may be called multiple times before nvme_mpath_uninit() (which is only called on nvme_free_ctrl()).
When nvme_mpath_init() is called multiple times, it overwrites the ana_log_buf pointer with a new allocation, thus leaking the previous allocation.
To fix this, free ana_log_buf before allocating a new one.
Fixes: 0d0b660f214dc490 ("nvme: add ANA support") Cc: stable@vger.kernel.org Reviewed-by: Sagi Grimberg sagi@grimberg.me Reviewed-by: Christoph Hellwig hch@lst.de Signed-off-by: Logan Gunthorpe logang@deltatee.com Signed-off-by: Keith Busch kbusch@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/nvme/host/multipath.c | 1 + 1 file changed, 1 insertion(+)
--- a/drivers/nvme/host/multipath.c +++ b/drivers/nvme/host/multipath.c @@ -715,6 +715,7 @@ int nvme_mpath_init(struct nvme_ctrl *ct }
INIT_WORK(&ctrl->ana_work, nvme_ana_work); + kfree(ctrl->ana_log_buf); ctrl->ana_log_buf = kmalloc(ctrl->ana_log_size, GFP_KERNEL); if (!ctrl->ana_log_buf) { error = -ENOMEM;